1. Field of the Invention
The present invention relates to an airship which floats for a long period of time without supply of energy.
2. Brief Description of the Prior Art
A fixed wing airplane, when used as a relay station or a wide range observatory platform, must be continuously flying, and is therefore possibly encounters a danger of fall down due to a trouble of an instrument during flying. On the other hand, an airship can float itself in the air and is prevented from such a danger. A power source therefor may be supplied from the ground through a microwave power transmission, or utilization of solar energy. The former requires a power transmitting base on the ground, and the flying range in which the flying body travels is limited so as to properly receive the electric power. Also, it is difficult to prevent electric wave trouble. In order to utilize the solar power in the daytime, it is only required to install a solar cell, but needs to install an electric battery for storing energy for the nighttime. The invention enables a long time travelling of an airship without carrying a heavy battery.
Airships include three types of rigid, nonrigid and semirigid. The rigid type has heavy weight, while the nonrigid has a structural problem due to its form in which the gondola is hung by a catenary curtain. The conventional semirigid airship, on the outside of which a keel is disposed, suffers from a large loss of air friction.